Reading a variable as a file

Wiggins has asked for the wisdom of the Perl Monks concerning the following question:

Background:
I have read an entire file into a variable ($email); undef $/; open INPT, "afile"; $email=<INPT>;...
Done massive substitutions all over the place with REGEXs and .csv file contents;
Now I want to read (and remove) only line #1 from $email into a new variable ($subject); and then remove all "white-space only" lines until the first 'used'(non-space characters) line.

Desired Solution:
I want to "open" the variable as a file, and manipulate it with File IO semantics in a record fashion (without having to write it out to disk and read it back in again).
Or is this just a foolish desire?

Comment on Reading a variable as a file Download Code

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Re: Reading a variable as a file by ikegami (Patriarch) on Nov 23, 2007 at 19:58 UTC
`use 5.008000; # open \$var open(my $fh, '<', \$var); while (<$fh>) { ... }` [download] or `while ($var =~ /(.*\n\|.+)/g) { ... }` [download]	[reply] [d/l] [select]
Re^2: Reading a variable as a file by codeacrobat (Chaplain) on Nov 23, 2007 at 20:14 UTC
Cool. I didn't know it also works with refs. An alternative is IO::Scalar. `use IO::Scalar; ### Open a handle on a string, read it line-by-line, then close it: $SH = new IO::Scalar \$var; while (<$SH>) { # ... } close $SH;` [download] `print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});`	[reply] [d/l] [select]
Re: Reading a variable as a file by fernandes (Monk) on Nov 23, 2007 at 21:56 UTC
Plese, let me know when you find the better solution. This subject interest to me as well.	[reply]
Re^2: Reading a variable as a file by FunkyMonk (Bishop) on Nov 23, 2007 at 23:20 UTC
ikegami's post gives you the best solution you're going to get. `open my $STR, "<", \$scalar;` [download] is the way to go	[reply] [d/l] [select]
Re: Reading a variable as a file by thezip (Vicar) on Nov 23, 2007 at 20:04 UTC
You may want to investigate Tie::File for this. Your wish is my commandline.	[reply]
Re^2: Reading a variable as a file by Dominus (Parson) on Nov 23, 2007 at 21:05 UTC
Unless I misunderstand the question, `Tie::File` is the wrong thing here. It makes a file look like an array. But I think what OP wants is to make a scalar look like a file. -- Mark Dominus Perl Paraphernalia	[reply]
Re^3: Reading a variable as a file by thezip (Vicar) on Nov 23, 2007 at 21:22 UTC
Yes, you're absolutely right. But to me, this problem seems to fall somewhere in the middle regarding how it should be handled... On the one hand, a scalar containing the entire file would make it easier to perform the numerous regex substitutions, while on the other hand, an array would make it easier to to shift off the required items. I think the point I was trying to make was that an "array" (instead of reading the entire file into a scalar) might be another approach to this problem. Update: After re-reading the OP's question, I now realize that I pretty much ignored the basic spec for the problem. Your wish is my commandline.	[reply]